Field
The present disclosure is generally related to antenna systems and more particularly, to a conformal broadband stacked multi-spiral antenna system configured for integration into a structural element of a mobile platform.
Related Art
Present day mobile platforms, such as aircraft (manned and unmanned, fixed-wing and rotary-wing), spacecraft, watercraft, and even land vehicles, often require the use of multiple antenna systems for transmitting and receiving electromagnetic signals. These signals include radar transmissions, signals intelligence (SIGINT) communications, Communication, Navigation, and Identification (CNI) signals, electromagnetic counter measures (ECM) and electronic warfare (EW) signals, and other sensor-processing applications. Each of these applications requires its own antenna system for the radiation and receipt of signals, and therefore many of these mobile platforms may have severe antenna crowding problems.
Conventional antennas may form protuberances that detract from the aerodynamics of the mobile platform. Also, if an antenna protrudes from the mobile platform body, the antenna may be exposed to accidental damage from ground personnel, environmental effects, or airborne objects. Typically weight is added to the mobile platform by the various components on which the antenna array is mounted. These components may include metallic gimbals, support structures, or other like substructures that add “parasitic” weight that is associated with the antenna array, but otherwise perform no function other than as a support structure for a portion of the antenna array. By the term “parasitic” it is meant weight that is associated with components of the support structure or antenna feed components that are not directly necessary for transmitting or receiving operations of the antenna array.
In the case of helicopters, finding an available area on the outside of a helicopter body to mount an antenna where the antenna will not interfere with a rotor, a stabilizer, or control surfaces of the helicopter can be difficult. There may be little available area on the helicopter body to mount such an antenna where the antenna can provide unobstructed coverage in all directions around the helicopter. For example, mounting a “towel bar” type antenna on a tail boom section of a helicopter makes use of available, largely unused space on the helicopter. However, towel bar type antennas extend outward from the tail boom section and may be subject to environmental damage, or damage by personnel servicing the helicopter when the helicopter is not in flight.
Therefore, there is a need for improving the design of antenna systems as well as their placement on mobile platforms to overcome the problems arising from the lack of space available for the various required antenna systems and also to avoid interference issues.